Total Inhalable Dust Research Articles

Application of Multiple Occupational Health Risk Assessment Models for Crystalline Silica Dust among Stone Carvers.

Silica is the most abundant substance on the Earth's crust and is a proven carcinogen. The aim of this study was to measure the occupational exposure of stone carvers to crystalline silica and to evaluate the health risks. Methods: This descriptive and analytical cross-sectional study was performed on 79 stone carvers. Inhalation air sampling was performed by the NIOSH7500 method and the amount of silica was determined by X-ray diffraction (XRD). Semi-quantitative and quantitative risk assessments were performed using the methods of the Singapore Department and the US Environmental Protection Agency (EPA), respectively. Mortality due to silicosis and lung cancer were estimated using the Manettej and Rice models. Data were analyzed using SPSS23 software. The mean exposure to total inhalable dust and crystalline silica among the stone carvers was 1.44 and 0.5 mg/m3, respectively. Exposure to total dust and silica was significantly higher than the occupational standard (P <0.0001). Stone carvers' exposure to silica was at very high-risk level, and the carcinogenicity of silica considering two cancer slopes was 7.40 × 10-6 and 3.12 × 10-7 and the risk of non-carcinogenicity was unacceptable. The mortality rate due to silicosis was between 3 and 12 people per thousand, and due to lung cancer was 150.24 people per thousand. Based on the results of risk assessment, serious control measures should be implemented in order to reduce workers' exposure to silica.

Evaluation of occupational exposure to wood dust among sawmill workers within the Gert Sibande District Municipality, South Africa.

Wood dust is regarded as one of the human carcinogen based on an increased risk of nasal and sinonasal cancer. This study was conducted in two sawmills to measure and determine the time-weighted average (TWA) exposure level to wood dust, and compare the results with the South African occupational exposure limit (OEL). Personal and area respirable and total inhalable wood dust samples were collected using calibrated Giliair-3 personal air sampling pump (Sensidyne, USA). Data was analysed using Microsoft Office Excel 2019 Analysis Tool Pak for a summary of descriptive statistics. Both the geometric means and standard deviation as well as the minimum and maximum values were calculated. The geometric mean = GM (geometric standard deviation = GSD) for personal respirable wood dust exposure at sawmill A was 0.9(4.8) mg/m3 while at sawmill B - 0.57(0.75) mg/m3. The GM(GSD) for personal total inhalable wood dust exposure at sawmill A was 0.37(0.94) mg/m3 while at sawmill B - 1.19(16.91) mg/m3. Besides that, the GM(GSD) for area respirable wood dust at sawmill A was 0.13(0.09) mg/m 3 , while at sawmill B - 0.8(0.6) mg/m3. Likewise, the GM(GSD) for area total inhalable wood dust at sawmill A was 0.13(0.16) mg/m3 while at sawmill B - 0.54(0.55) mg/m3 . Results for the majority of samples were below the OEL. Workers smoking tobacco or cigarettes should be encouraged to stop smoking since smoking, especially when associated with exposure to wood dust, may increase the risk of respiratory health symptoms.

HBM4EU Chromates Study: Determinants of Exposure to Hexavalent Chromium in Plating, Welding and Other Occupational Settings.

Work-related exposures in industrial processing of chromate (chrome plating, surface treatment and welding) raise concern regarding the health risk of hexavalent chromium (Cr(VI)). In this study, performed under the HBM4EU project, we focused on better understanding the determinants of exposure and recognising how risk management measures (RMMs) contribute to a reduction in exposure. HBM and occupational hygiene data were collected from 399 workers and 203 controls recruited in nine European countries. Urinary total chromium (U-Cr), personal inhalable and respirable dust of Cr and Cr(VI) and Cr from hand wipes were collected. Data on the RMMs were collected by questionnaires. We studied the association between different exposure parameters and the use of RMMs. The relationship between exposure by inhalation and U-Cr in different worker groups was analysed using regression analysis and found a strong association. Automatisation of Cr electroplating dipping explained lower exposure levels in platers. The use of personal protective equipment resulted in lower U-Cr levels in welding, bath plating and painting. An effect of wearing gloves was observed in machining. An effect of local exhaust ventilation and training was observed in welding. Regression analyses showed that in platers, exposure to air level of 5 µg/m3 corresponds to U-Cr level of 7 µg/g creatinine. In welders, the same inhalation exposure resulted in lower U-Cr levels reflecting toxicokinetic differences of different chromium species.

Potential human inhalation exposure to soil contaminants in urban gardens on brownfields sites: A breath of fresh air?

Urban gardening has been experiencing increased popularity around the world. Many urban gardens are located on sites that may be contaminated by trace elements or organic compounds due to previous use. The three main exposure pathways to the human body for soil contaminants are (a) ingestion of soil directly, (b) consumption of produce containing or superficially contaminated with a contaminant, (c) and inhalation of soil dust. The first two modes have received much attention; however, the contribution of the inhalation route has not been investigated adequately. Two inhalation risk studies were carried out in urban gardens located in Kansas City, MO, by collecting dust while 25-m2 plots were rototilled. Microclimatic variables were monitored, and total inhalable dust mass was determined using a personal sampling train including a small pump and air filter. Soil lead (Pb) concentration was assessed at both sites. For Study 1, particle size distribution of collected particles was estimated through analysis of scanning electron microscope images of filters. Little dust was collected at either site. Most particles captured, however, appeared to be <4μm in diameter. The amount of dust emitted was correlated with soil moisture. Tilling reduced soil aggregate size and blended soil, resulting in a more homogeneous distribution of Pb. Dust inhalation while tilling is likely not a major Pb exposure risk for gardeners, but given the preponderance of very small particles in what was captured, care should be taken to prevent dust from entering the respiratory system.

The Measurement of Wood in Construction Dust Samples: A Furnace Based Thermal Gravimetric Approach.

A furnace-based thermal gravimetric method was developed to measure wood in inhalable construction dust. The application of this method showed that reliance on the inhalable concentrations alone may substantially overestimate carpenters' exposures to wood dust at construction worksites. Test samples were prepared by collecting aerosols of gypsum, calcite, quartz, concrete, and wood dust onto quartz fibre filters using the Button inhalable sampler. The average difference between the measured and loaded mass of wood is 2% over the whole analytical range. Ninety percent of thermogravimetric measurements on all test samples (n = 35) were 13% or less. The limit of detection was measured as 0.065 mg. The thermal gravimetric method was applied to samples collected from four new build construction sites and one shop fitting worksite. The workplace inhalable wood dust results ranged from 15% to 104% of the total inhalable dust values. In addition, an x-ray diffraction (XRD) Rietveld method was applied as a complimentary approach to explain the composition of the remaining inhalable dust. Most combined thermal gravimetric and XRD measurements were within 10% of the total inhalable dust mass values, determined gravimetrically. Ninety-five percent were within 26%. The median proportion of mineral dust containing gypsum, calcite, quartz, dolomite, or rutile was 30%. The proportion of mineral dust on individual filters varied considerably.

Coal Airborne Particulates and its Relationship with Human Health

Airborne particles emitted from coal-fired power plant affects human behaviour. Two times 8 hours airborne particulate personal outdoor sampling through 7-hole and cyclone samplers has been conducted nearby a coal-fired power plant and a gas power plant. Two samplers used were 7-hole and cyclone. This research found that 58.25 per cent (%) from total inhalable dust exceeded the outdoor PM10 DOE 24 hours Malaysia Standard. The study also has found that the percentage ratio of respirable towards inhalable dust is at 51.7%. Finally, effects of coal particles to human health were identified.

Experimental study on effects of drilling parameters on respirable dust production during roof bolting operations

ABSTRACTUnderground coalmine roof bolting operators exhibit a continued risk for overexposure to airborne levels of respirable coal and crystalline silica dust from the roof drilling operation. Inhaling these dusts can cause coal worker's pneumoconiosis and silicosis. This research explores the effect of drilling control parameters, specifically drilling bite depth, on the reduction of respirable dust generated during the drilling process. Laboratory drilling experiments were conducted and results demonstrated the feasibility of this dust control approach. Both the weight and size distribution of the dust particles collected from drilling tests with different bite depths were analyzed. The results showed that the amount of total inhalable and respirable dust was inversely proportional to the drilling bite depth. Therefore, control of the drilling process to achieve proper high-bite depth for the rock can be an important approach to reducing the generation of harmful dust. Different from conventional passive engineering controls, such as mist drilling and ventilation approaches, this approach is proactive and can cut down the generation of respirable dust from the source. These findings can be used to develop an integrated drilling control algorithm to achieve the best drilling efficiency as well as reducing respirable dust and noise.

Environmental characterization of a coffee processing workplace with obliterative bronchiolitis in former workers

ABSTRACTObliterative bronchiolitis in five former coffee processing employees at a single workplace prompted an exposure study of current workers. Exposure characterization was performed by observing processes, assessing the ventilation system and pressure relationships, analyzing headspace of flavoring samples, and collecting and analyzing personal breathing zone and area air samples for diacetyl and 2,3-pentanedione vapors and total inhalable dust by work area and job title. Mean airborne concentrations were calculated using the minimum variance unbiased estimator of the arithmetic mean.Workers in the grinding/packaging area for unflavored coffee had the highest mean diacetyl exposures, with personal concentrations averaging 93 parts per billion (ppb). This area was under positive pressure with respect to flavored coffee production (mean personal diacetyl levels of 80 ppb). The 2,3-pentanedione exposures were highest in the flavoring room with mean personal exposures of 122 ppb, followed by exposures in the unflavored coffee grinding/packaging area (53 ppb). Peak 15-min airborne concentrations of 14,300 ppb diacetyl and 13,800 ppb 2,3-pentanedione were measured at a small open hatch in the lid of a hopper containing ground unflavored coffee on the mezzanine over the grinding/packaging area. Three out of the four bulk coffee flavorings tested had at least a factor of two higher 2,3-pentanedione than diacetyl headspace measurements.At a coffee processing facility producing both unflavored and flavored coffee, we found the grinding and packaging of unflavored coffee generate simultaneous exposures to diacetyl and 2,3-pentanedione that were well in excess of the NIOSH proposed RELs and similar in magnitude to those in the areas using a flavoring substitute for diacetyl. These findings require physicians to be alert for obliterative bronchiolitis and employers, government, and public health consultants to assess the similarities and differences across the industry to motivate preventive intervention where indicated by exposures above the proposed RELs for diacetyl and 2,3-pentanedione.

COAL-FIRED POWER PLANT AIRBORNE PARTICLES IMPACT TOWARDS HUMAN HEALTH

The explosion of global warming and climate change occurs parallel to the raise rise of earth development. These phenomena happen due to the deterioration of atmospheric environment rooted from human activity. Ranges of air pollutants had been discovered. However, this research focuses on airborne particles in particular that comes from the emissions of coal. Recently, Malaysia electricity demand is raising and leads to the diversification of its sources towards the non-renewable energy. Manjung coal-fired power plant emission had been recognised as one of the potential anthropogenic sources of airborne particles. 8-hours airborne particles sampling had been done at Manjung Power Plant in March and July 2011 with 7-hole sampler at 2 L/min air flow and cyclone sampler at 2.2 L/min airflow. This research found that total inhalable dust exceeds 96.78 %; PM10 standard of 0.15mg/m3.This study also found that the percentage ratio of respirable towards total inhalable dust is 33.49%. This study also found that, as the temperature increases, the airborne particles concentration also increases. It is believed that the smaller offers particulate higher degree of illness. Thus, it is believed, the airborne particles dissemination from its sources is affected by the climate of an environment. Whichcan be deposited into deeper part of lung and provide adverse health impact towards the public or residence of surrounding coal-fired power plant neighbourhood area, generally and coal workers, specifically.

INHALABLE AND RESPIRABLE DUST FROM COAL-FIRED POWER PLANT

Among the anthropogenic air pollutant that lead to the global warming, this research focuses on the inhalable dust and respirable dust that comes from the emissions of coal. Recently, the demand of electricity supply in Malaysiais raising and leads to the diversification of its resources towards the non-renewable energy. Coal-fired power plant emission had been recognized as one of the manmade sources of particulate matter. 8-hours personal particulate matter sampling had been done at a coal-fired power plant with 7-hole sampler at 2 L/min air flow and cyclone sampler at 2.2 L/min air flow. This study found that 96.78 % of the result from total inhalable dust exceeds the PM10DOE Malaysia standard of 0.15mg/m3. The percentage ratio of respirable towards total inhalable dust is 50.25%. Further analysis showed that as the temperature increases, the particulate matter concentration also increases. It is believed that the smaller particles offer higher degree of human health risk. The particulate from coal with aerodynamic diameter of 2.5 micron and lesser can be deposited into deeper part of lung and provide adverse health impact towards the public or residence of surrounding coal-fired power plant location area, generally and coal-fired power plant workers, in specific.

Occupational Exposure to Wood Dust and Respiratory Health Status of Sawmill Workers in South-South Nigeria

Ill-health from wood dust inhalation results in decreased work output and increased morbidity. Despite the potentially hazardous nature of the work, there has been little attention given to the state of health and safety of the workers in this industry in Nigeria. The study sought to investigate the prevalence of respiratory symptoms and lung function abnormalities from occupational exposure to wood dust among sawmill workers, and assess wood dust concentration in sawmills in Egor Local Government Area of Edo State. A cross-sectional analytical survey involving 227 workers from 17 sawmills recruited through a one stage cluster sampling technique and matched for age and height with 227 workers in water bottling companies in the same locality was carried out. Structured questionnaires and spirometry were used for data collection. Dust monitoring in the both study and comparison sites was carried out with the aid of a gravimetric dust sampler. Data analysis was done using SPSS version 15 and PEPI version 10. Ethical clearance was obtained from the University of Benin Teaching Hospital. Prevalence of respiratory symptoms in the study group was: cough 46.7%, phlegm expectoration 50.2%, wheeze 5.3%, chest tightness 10.1%, chest pain 5.7% and breathlessness 7.5%. Respiratory symptoms were of significantly higher prevalence among the study than the comparison group. Mean value for total and inhalable dust was significantly higher (p = 0.00 and p =0.01 respectively) higher in the study than in the comparison sites. There was no significant difference (p = 0.16) between both sites for mean values of respirable dust. Sawmill workers had a high prevalence of respiratory symptoms particularly cough and phlegm production, and a higher exposure to total suspended and inhalable dust compared to suitably matched respondents. The results have strong implications for improved dust control in the wood industry.

Occupational exposure in the fluorescent lamp recycling sector in France

The fluorescent lamp recycling sector is growing considerably in Europe due to increasingly strict regulations aimed at inciting the consumption of low energy light bulbs and their end-of-life management. Chemical risks were assessed in fluorescent lamp recycling facilities by field measurement surveys in France, highlighting that occupational exposure and pollutant levels in the working environment were correlated with the main recycling steps and processes.The mean levels of worker exposure are 4.4mg/m3, 15.4μg/m3, 14.0μg/m3, 247.6μg/m3, respectively, for total inhalable dust, mercury, lead and yttrium. The mean levels of airborne pollutants are 3.1mg/m3, 9.0μg/m3, 9.0μg/m3, 219.2μg/m3, respectively, for total inhalable dust, mercury, lead and yttrium. The ranges are very wide. Surface samples from employees’ skin and granulometric analysis were also carried out. The overview shows that all the stages and processes involved in lamp recycling are concerned by the risk of hazardous substances penetrating into the bodies of employees, although exposure of the latter varies depending on the processes and tasks they perform. The conclusion of this study strongly recommends the development of a new generation of processes in parallel with more information sharing and regulatory measures.

Fine Particulates Matter (PM2.5) from Coal-fired Power Plant in Manjung and its Health Impacts

Fine particulates matter (PM2.5) emitted from coal-fired power plant can affect human behaviour. Two times 8hours airborne particulates personal outdoor sampling through 7-hole and cyclone samplers has been conducted nearby Manjung Power Plant and Lumut Power Plant. Two samplers used are the 7-hole and cyclone. This research found that 58.25 per cent (%) from total inhalable dust exceeded the outdoor PM10 DOE 24hours Malaysia Standard. The study also has found that the percentage ratio of respirable towards inhalable dust is at 51.7%. Finally, literature reviews linking coal fine particulates matter to the health impact are done to comprehend this study.

Workplace Exposure to Bioaerosols in Podiatry Clinics

The aim of this study was to design and execute a pilot study to collect information on the personal exposure levels of podiatrists to microbial hazards in podiatry clinics and also to assess health and safety knowledge within the sector using a questionnaire survey. A self-report quantitative questionnaire dealing with health and safety/health issues was issued to 250 podiatrist clinics. Fifteen podiatry clinics were randomly recruited to participate in the exposure study. Concentrations of airborne bacteria, fungi, yeasts, and moulds were assessed using a six-stage viable microbial cascade impactor. Personal samples of total inhalable dust and endotoxin were measured in the breathing zone of the podiatrist. A questionnaire response rate of 42% (N = 101) was achieved. Thirty-two per cent of respondents indicated that they had a respiratory condition; asthma was the most prevalent condition reported. The most frequently employed control measures reported were use of disposable gloves during patient treatments (73.3%), use of respiratory protective equipment (34.6%), use of protective aprons (16.8%), and eye protection (15.8%). A total of 15.8% of respondents used mechanical room ventilation, 47.5% used nail drills with local exhaust ventilation systems, and 11% used nail drills with water spray dust suppression. The geometric mean concentrations of bacteria, Staphylococci, fungi, and yeasts/moulds were 590, 190, 422, and 59 CFU m(-3), respectively. The geometric mean endotoxin exposure was 9.6 EU m(-3). A significant percentage of all the bioaerosols that were in the respirable fraction was representative of yeasts and moulds (65%) and Fungi (87%). Even if statistical analysis of data is limited by low sample numbers, this study showed that the frequency of cleaning and use of RPE varied between clinics sampled, and it is likely that refresher health and safety training focusing on health and safety hazards inherent in podiatry work and practical control measures is warranted.

Respiratory symptoms in insect breeders

A number of specialist food suppliers in the UK breed and distribute insects and insect larvae as food for exotic pets, such as reptiles, amphibians and invertebrates. To investigate the extent of work-related (WR) symptoms and workplace-specific serum IgE in workers potentially exposed to a variety of biological contaminants, including insect and insect larvae allergens, endotoxin and cereal allergens at a UK specialist insect breeding facility. We undertook a study of respiratory symptoms and exposures at the facility, with subsequent detailed clinical assessment of one worker. All 32 workers were assessed clinically using a respiratory questionnaire and lung function. Eighteen workers consented to provide serum for determination of specific IgE to workplace allergens. Thirty-four per cent (11/32) of insect workers reported WR respiratory symptoms. Sensitization, as judged by specific IgE, was found in 29% (4/14) of currently exposed workers. Total inhalable dust levels ranged from 1.2 to 17.9 mg/m(3) [mean 4.3 mg/m(3) (SD 4.4 mg/m(3)), median 2.0 mg/m(3)] and endotoxin levels of up to 29435 EU/m(3) were recorded. Exposure to organic dusts below the levels for which there are UK workplace exposure limits can result in respiratory symptoms and sensitization. The results should alert those responsible for the health of similarly exposed workers to the potential for respiratory ill-health and the need to provide a suitable health surveillance programme.

Dust, Noise and Chemical Solvents Exposure of Workers in the Wooden Furniture Industry in South East Asia

A study was carried out to evaluate the dust, noise and chemical solvents exposure among workers in the wooden furniture industry in the South East Asian region comprising Malaysia, Thailand, Indonesia and Vietnam. A total of 30 factories were selected from each country for the study. Air quality samples at the machining and sanding workstations were measured using the micro-orifice uniform deposit impactor (MOUDI), which separated the particles into different sizes. The results showed that the average dust concentration in the machining section was lower than that in the sanding section, but total inhalable dust particles of less than 10 μm in diameter, was less than 25% by weight. Portable noise-level measurements showed that the rough-milling operations recorded the highest noise-level in the furniture factories in the region. Personal dosimeter measurement results show that 43% of the workers were exposed to noise-levels higher than the permissible limit, with 34.7% of the workers suffered from hearing handicap. The study also found that the current exposure levels for both chemical solvents and formaldehyde in the wooden furniture industry in the countries within the South East Asian region were higher than the Permissible Exposure Levels (PEL). Therefore, it was apparent that despite the existent of a comparable Occupational Health and Safety regulations in the region, its implementation and enforcement within the wooden furniture industry must be improved to ensure the workers safety and health.

Characterization and Assessment of Dermal and Inhalable Nickel Exposures in Nickel Production and Primary User Industries

The aim of this study was to measure the levels of nickel in the skin contaminant layer of workers involved in specific processes and tasks within the primary nickel production and primary nickel user industries. Dermal exposure samples were collected using moist wipes to recover surface contamination from defined areas of skin. These were analysed for soluble and insoluble nickel species. Personal samples of inhalable dust were also collected to determine the corresponding inhalable nickel exposures. The air samples were analysed for total inhalable dust and then for soluble, sulfidic, metallic, and oxidic nickel species. The workplace surveys were carried out in five different workplaces, including three nickel refineries, a stainless steel plant, and a powder metallurgy plant, all of which were located in Europe. Nickel refinery workers involved with electrolytic nickel recovery processes had soluble dermal nickel exposure of 0.34 microg cm(-2) [geometric mean (GM)] to the hands and forearms. The GM of soluble dermal nickel exposure for workers involved in packing nickel salts (nickel chloride hexahydrate, nickel sulphate hexahydrate, and nickel hydroxycarbonate) was 0.61 microg cm(-2). Refinery workers involved in packing nickel metal powders and end-user powder operatives in magnet production had the highest dermal exposure (GM = 2.59 microg cm(-2) soluble nickel). The hands, forearms, face, and neck of these workers all received greater dermal nickel exposure compared with the other jobs included in this study. The soluble nickel dermal exposures for stainless steel production workers were at or slightly above the limit of detection (0.02 microg cm(-2) soluble nickel). The highest inhalable nickel concentrations were observed for the workers involved in nickel powder packing (GM = 0.77 mg m(-3)), although the soluble component comprised only 2% of the total nickel content. The highest airborne soluble nickel exposures were associated with refineries using electrolytic processes for nickel recovery (GM = 0.04 mg m(-3) total nickel, containing 82% soluble nickel) and those jobs involving contact with soluble nickel compounds (GM = 0.02 mg m(-3) total nickel content, containing 76% soluble nickel). The stainless steel workers were exposed to low concentrations of relatively insoluble airborne nickel species (GM = 0.03 mg m(-3) total nickel, containing 1% soluble nickel). A statistically significant correlation was observed between dermal exposures for all anatomical areas across all tasks. In addition, the dermal and inhalable (total) nickel exposures were similarly associated. Overall, dermal exposures to nickel, nickel compounds, and nickel alloys were relatively low. However, exposures were highly variable, which can be explained by the inconsistent use of personal protective equipment, varying working practices, and different standards of automation and engineering controls within each exposure category.

Exposure to particulate matter on an Indian stone-crushing site

Background/objectives:A large number of labourers work in the stone-crushing industry in India. Many of these workers are also exposed to high levels of particulate matter in their homes from the...

Mineral dust exposure in young Indian adults: an effect on lung growth?

Background/objective:Long-term occupational exposure to mineral dusts including quartz is known to cause pneumoconiosis but little is known about the effects of such exposure during the period of lung development in...

Preventing baker's asthma: an alternative strategy

Although baker's asthma has attracted considerable research interest over the last 30 years, success in its prevention has been slow to achieve. This paper describes the results of an alternative preventive strategy, based on an observation that the excess of sensitization in bread bakers is largely due to IgE-mediated allergy to fungal amylase, contained in bread improvers. The practical application of the strategy has been to limit bread improver exposures to <1 mg/m3 [8 h time-weighted average (TWA)], whilst exposures to all other ingredients, including flour, have been limited to <10 mg/m3 (8 h TWA). The paper describes the findings of in-house respiratory health surveillance and dust sampling programmes, from a UK food company whose primary interests are milling and baking, over the period following the introduction of the strategy to target the reduction in bread improver exposure. Over the 10 year period of surveillance, the incidence of symptomatic sensitization in the bread baking sector (2240 per million employees per annum) was greater than for the other flour-using groups (330 per million employees per annum), despite broadly similar total inhalable dust exposures. There was an overall reduction in the incidence of new cases of symptomatic sensitization, from 2085 per million employees per year in the first 5 years of the surveillance programme, to 405 per million employees per year in the subsequent 5 years. The strategy of targeting bread improver exposure is an effective approach for the prevention of new cases of symptomatic sensitization in bread bakeries.